Nucleic acid hybridization is based on the specific binding between complementary DNA chains, which are currently broadly used for gene expression analysis, gene phenotype analysis and clinical diagnosis etc. For conventional static nucleic acid hybridization represented by microarray chip, the hybridization process simply relies on molecular diffusion, that is, target molecules must diffuse from the solution to the substrate surface coated with probe, and then recognize and interact with the probe. However, the hybridization process may cost hours due to the extremely small diffusion coefficient of a target nucleic acid molecules. Additionally, the sample loading for such microarray chip is mainly realized by using delicate sampling device such as pipette, which greatly limits the use of microarray chip and needs highly qualified operators.
At present, a number of hybridization chips have been developed based on microfluidics to achieve shorter hybridization time and lower sample loss, which, depending on different mechanism, includes dynamic hybridization chip platforms based on electric force or magnetic stirring, mixing by vibration, continuous flow or circulation flow. However, due to the disadvantages such as complex chip preparation process, high sample loss, expensive external auxiliary apparatus, complicated operation process and incapability of multi-sample analysis, such techniques are still in research in laboratory, and can not be largely used or popularized.